A new update is available for Fedora Core - [SECURITY] Fedora Core 4 Update: pam-0.79-9.6. Here the announcement:

Fedora Update Notification
FEDORA-2005-1031
2005-10-27
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Product : Fedora Core 4
Name : pam
Version : 0.79
Release : 9.6
Summary : A security tool which provides authentication for applications.
Description :
PAM (Pluggable Authentication Modules) is a system security tool that
allows system administrators to set authentication policy without
having to recompile programs that handle authentication.

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Update Information:

This update fixes a security bug in unix_chkpwd allowing
brute force attacks against passwords in /etc/shadow by a
regular user when SELinux is enabled.
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* Wed Oct 26 2005 Tomas Mraz <tmraz@redhat.com> 0.79-9.6
- fixed CAN-2005-2977 unix_chkpwd should skip user verification only if
run as root (#168181)
- link pam_loginuid to libaudit
- remove spurious glib2 dependency
- support no tty in pam_access (#170467)
- support new kernel limits and unlimited limit value in pam_limits (#171546)


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This update can be downloaded from:
http://download.fedora.redhat.com/pub/fedora/linux/core/updates/4/

fb348c5be5d8f694cdbd927681150989 SRPMS/pam-0.79-9.6.src.rpm
4a06122544169a7549639fa52be91bcd ppc/pam-0.79-9.6.ppc.rpm
edf3fc81ac4dfddf44f25dd37142b23c ppc/pam-devel-0.79-9.6.ppc.rpm
873dca1bc06450ede87a40b9d0241398 ppc/debug/pam-debuginfo-0.79-9.6.ppc.rpm
054d2fe06507a3c45c7ef8bcf8a595ac ppc/pam-0.79-9.6.ppc64.rpm
c7a3db12973f5182739d6adae0b25555 ppc/pam-devel-0.79-9.6.ppc64.rpm
6774937168a148b9e63e54711c26c790 x86_64/pam-0.79-9.6.x86_64.rpm
649b875ec7894c2fd855abb9a6547ef0 x86_64/pam-devel-0.79-9.6.x86_64.rpm
a70f55b7f8ce114052362e167984fdb0 x86_64/debug/pam-debuginfo-0.79-9.6.x86_64.rpm
6674a4ea75709a1e5c7f905e617db12b x86_64/pam-0.79-9.6.i386.rpm
f535f175a757f0d7b1dc66b1538fcd1c x86_64/pam-devel-0.79-9.6.i386.rpm
6674a4ea75709a1e5c7f905e617db12b i386/pam-0.79-9.6.i386.rpm
f535f175a757f0d7b1dc66b1538fcd1c i386/pam-devel-0.79-9.6.i386.rpm
d4ec56ab2def5974a103495169442c4c i386/debug/pam-debuginfo-0.79-9.6.i386.rpm

This update can also be installed with the Update Agent; you can
launch the Update Agent with the 'up2date' command.